The present invention relates to a digital signal recording and reproducing apparatus which is capable of recording and reproducing an audio digital signal alone or together with a video signal in a video tape recorder (hereinafter referred to as the VTR).
In the conventional apparatus in which an audio digital signal is recorded in a VTR, the sampling frequency of the audio signal is selected to be an integral multiple of the vertical synchronous signal of the video signal to record the audio digital signal in a predetermined number of samples during one vertical scanning period (hereinafter referred to as a "field"). In the case of a PCM audio processor according to the EIAJ (Electronic Machinery Industry Association of Japan) standards, for instance, the audio sampling frequency for the VTR of an NTSC system is set to the frequency of 44,056 KHz, that is 735 times higher than the vertical synchronous signal (60.times.1000/1001 .apprxeq. 59.94 Hz). In this case, the audio digital signal of 735 samples per channel is recorded in a signal field of the VTR.
There may be some cases, however, where the audio sampling frequency is not an integral multiple of the vertical synchronous signal. In a PCM recorder used for business purposes for which a sampling frequency of 48 KHz is recommended according to AES (Audio Engineering Society) Standards, for example, an audio digital signal of 800.8 samples is recorded for each channel in a field, dividing one sample, if recorded in a VTR of an NTSC system. When an audio digital signal of 800.8 samples is recorded in a field this way, it is necessary to divide a sample, thereby complicating the circuit configuration. Further, an editing process for each field becomes difficult.